Laparoscopic surgical procedures have been around for many years and have become more available due to advances in technology relating to the laparoscope or video imaging system. They are much less intrusive to the patient than typical open surgical procedures. While an open surgical procedure may involve one primary incision that is at least 6-20 centimeters long, a laparoscopic procedure typically uses smaller incisions, each only around 5-11 millimeters long. In open surgery, the surgeon cuts muscle. In laparoscopic surgery, the surgeon generally does not cut muscle. Because they are less intrusive than open surgical procedures, laparoscopic procedures have resulted in much shorter surgical procedures and recovery times.
Laparoscopic procedures have typically involved insufflation of the abdominal or peritoneal cavity with carbon dioxide and/or other gases in order to create a pneumoperitoneum. The pneumoperitoneum establishes an open space inside the peritoneal cavity to enable the surgeon to move the laparoscope and laparoscopic instruments around the inside and perform surgical and diagnostic procedures.
Typically, the pneumoperitoneum is established by puncturing the abdominal wall with a Veress needle and injecting gas from an insufflator through the Veress needle into the peritoneal cavity to a pressure of around 12 mm Hg.
After insufflation, a trocar is advanced through the opening in the abdominal wall and into the peritoneal cavity. The trocar includes a tube or cannula that usually has a gaseous seal to contain the carbon dioxide within the peritoneal cavity and maintain insufflation. The cannula is used for insertion of other medical instruments such as a laparoscope therethrough and into the peritoneal cavity.
There may be certain difficulties associated with insufflation of the peritoneal cavity. A major consideration is operative and postoperative pain which patients may experience in the abdomen or shoulder area due to migrating gas. This occurs when insufflation causes excess gas pressure in the peritoneal cavity. Excess gas pressure may also compress the pleural cavities thus making respiration difficult. Other possible difficulties associated with insufflation in laparoscopic surgery include subcutaneous emphysema, blood vessel penetration, etc.
The attendant difficulties of insufflation have led to alternatives to insufflation wherein an open space is established by elevating the abdominal wall with a mechanical lift. The lift is introduced through an opening in the abdominal wall into the peritoneal cavity before establishing an open space. The lift is elevated mechanically in order to distend the abdominal wall. When the abdominal wall is distended, ambient air enters the abdomen through the puncture opening in the abdominal wall and an open space at or near ambient air pressure is established.
By establishing an open space at ambient air pressure, insufflation and the concomitant need for gaseous seals in endoscopic instruments and trocars for maintaining a relatively high gas pressure in the peritoneal cavity is eliminated. Thus the attendant difficulties of insufflation, as well as the need for costly equipment, is eliminated.
The prior art includes several abdominal lift structures. Origin Medsystems, Inc. of Menlo Park, Calif. markets a lift under the trademark Laparofan.TM.. It has two radially extending blades that are rotatable. The blades are closed together for initial insertion into the abdominal cavity. After insertion, the blades are spread or fanned. When the lift is elevated, the blades contact and elevate the inner surface of the abdominal wall. Origin's device is described in International Patent Application PCT/FR91/4456.
Societe 3X, a French company, markets an abdominal lift and support structure. This lift is shown and described in International Patent Application PCT/FR91/227. It contains a series of curves forming a generally triangular shape. The tip of the lift is turned downwardly slightly. The support structure has a crane and boom design. Gross adjustments are made by sliding the supporting leg and the boom within their respective holders. A mechanical screw-jack is used for fine adjustment.
International Patent Application PCT/FR91/227 describes an abdominal lift having various curves in different directions. U.S. Pat. No. 5,183,033 describes a method for lifting an abdominal wall with a set of linear and non-linear abdominal lifts. International Patent Application PCT/US/4392 describes a variety of mechanical rods, arms and/or balloons for mechanically lifting an abdominal wall during laparoscopic surgery.
There are some other prior art structures for elevating and/or supporting abdominal lifts in laparoscopic surgery. U.S. Pat. No. 5,183,033 illustrates support structures using winches or U-shaped bars for use in laparoscopic surgery.
Further, there are a number of prior art support structures for supporting mechanical lifts used in open surgery. For example, see U.S. Pat. Nos. 5,109,831 and 4,143,652.
An improved abdominal lift device is disclosed in U.S. patent application Ser. No. 08/108,895, filed on Aug. 18, 1993, and assigned to the same assignee as the present invention. The device includes a curved portion that defines a substantial portion of a circle. A spoke portion extends radially inwardly from the curved portion and an upstanding member extends upwardly from the spoke portion. The upstanding member is connectable to a support structure which elevates and supports the abdominal lift device.
The ease of operation of most of these prior art lift devices without any damage to internal viscera is limited. There is a need for lift devices that may be directed through a small opening in an abdominal wall and subsequently deployed within the abdominal cavity. There is also a need for an alternative surgical lift method and device that may be used by doctors in a hospital operating room and in their offices for diagnostic purposes. It is anticipated that such diagnostic procedures may include the use of a Veress needle-type device having optical capabilities without the use of a general anesthesia.